Vacuum fuel-feed device for aerial-vessel engines.



W. JAY.

VACUUM FUEL FEED DEVICE FOR AERIAL VESSEL ENGINES.

APPLICATION FILED mm. I918.

1 83,524. Pmma Nov. 1918.

MA MI TAN/Y WEBB JAY, or CHICAGO, ILLINOIS.

VACUUM FUEL-FEED DEVICE FOR AERIAL-VESSEL .ENGIN ES.

Specification of Letters Patent.

Patented Nov. 5, 1918.

Application filed January 2, 1918. Serial No. 209,872.

To all whom it may concern:

Be it known that I, WEBB JAY, a citizen of the United States, residingat Chicago, in the county of Cook and State of Illinois,

have invented certain new and useful Improvements in Vacuum Fuel-FeedDevices for Aerial-Vessel Engines, of which the following is aspecification, reference being had to the accompanying drawlngs, forminga part thereof.

The purpose of this invention is to provide an improvedexpedient forproducing the partialvacuum required in a vacuum fuel feed device for aninternal combustion engine of an aeroplane or other aerial vessel. Itconsists in the elements and features of construction shown anddescribed, as indicated in the claims.

In the drawings: 4

Figure 1 is -a side elevation of an aerial vessel, showing inapproximately relative position the propeller and engine thereof, andshowing the engine equipped with a vacuum fuel feed device embodyingthis invention'.

Fig: 2 is adetail view showing upon a larger scale and in verticalsection the vacuum chamber of the vacuum feed device and the vacuum ductleading therefrom, to-

gether with a portion of the fuel feed tank into which the vacuumchamber discharges.

Fig. 3 is a fragmentary side elevation of an aerial vessel showing analternative mounting of the vacuum feed device and tank.

In the drawings Fig. 1 indicates conventionally a bi-plane, A, withupper and lower planes, B and C, respectively, and propeller,

. D. Mounted within the fuselage is shown in dotted outline the engine,E, and a fuel feed tank, 1, connected with the carburetor, F.

Fig. 2 shows, on a larger scale, a vacuum feed device associated withthe tank, 1, and

" comprising a vacuum chamber, 2, suspended within the tank, 1, andinclosin'g a float, 3, connected by a familiar form of linkage withvalves, 4 and 5, controlling respectively the atmospheric inlet, 6 andvacuum duct, 7. A fuel supply pipe, 8, leading from a main fuel tanklocated at any convenient point on the margin lower than the feed tank,1, and not shown in the drawings,-'discharges into the upper portion ofthe vacuum cham-' her, 2, and an atmospheric vent, 9, leads from the topof tank, 1, preferably to the said main fuel tank to'permit overflowfrom tank, 1, to the main tank in case of overfilling of said feedtank, 1. In the usual manner, the snap action or linkage, 10, is adaptedto place the chamber, 2, alternately under dominance of suction andpressure for causing inflow of liquid fuel through pipe, 8-, anddischarge of such fuel to the tank or reservoir, 1, by virtue of thealternatlng closing and opening of valves, 4 and 5.

The present invention relates among other things to means for producingthe necessary 4 partial vacuum in the chamber, 2, and this meansconslsts in the disposition of duct, 7, with its opening in a region oflow pressure, or 1n a direction such that the air current produced bythe propeller,D, moving rearwardly through the Venturi tube may causeentrainment of air in duct, 7, resulting in reduced pressure therein.For this purpose the means preferably includes a Venturi tube, 11 openforwardly toward the propeller, D, and as shown in Fig. 1, mounted ustabove the fuselage to receive the current from said propeller. As seenin Fig. 2, the duct, 7, opens into the Venturi just beyond theapex orplane of greatest restrict1on lIldlCfltGd: at 12, this being in a regionof reduced pressure, by reason of the rapidly expandlng cross-sectionofthe Venturi tube beyond its apex with relation to the air movementthrough said tube. It will be understood that the Venturi tube servesmerely to ncrease the entraining effect of the a1r current producedbythe propeller that said current, without such increase 111 its velocty, might be utilized under certam condltlons for producing theentrainment and consequent partial vacuum.

As an alternative construction, Fig. 3 shows the reservoir, 1, mountedjust under the upper plane, B, with theventuri, 11, openmg at the undersideof the plane and dlscharging above the latter so as to besusceptible to the high air pressure at the under slde of the plane, aswell as the air current from the propeller, D, and by furnishing a ventthrough the plane for such pressure to create a high velocity currentfrom which vacuum may be derived for the vacuum chamber, 2, within thetank, 1.

In order that the liquid derived by suc-l tion from the main fuel tankmay be dis- 'i charged from" the vacuum chamber, 2, very promptly uponthe intermission of the suction and the admission of the atmospheric theside of the plane of greatest constriction toward the propeller. Onaccount of the constriction of the Venturi tube, there is a highpressure produced in this region,-

and, upon the opening of the air valve, 4, this relatively high pressureinstead. of nor mal atmospheric pressure is admitted to the chamber, 2,for discharging the liquid fuel therefrom into the reservoir, 1. Thismakes it possible to fill the reserve chamber, 1, to any height forwhich the pressure derived from the Venturi is adequate, instead ofbeing limited to the height at which float 3, in chamber, 2, operatesthe snap action device, 10, to 'close the suction valve, 5,'as would bethe case if only atmospheric pressure were admitted to the chamber, 2,by opening of valve, 4. The tank, 1, may therefore be extended to occupyas great space longitudinally of the aeroplane as may be foundconvenient, and itsstorage space extended up as high as the top of thevacuum chamber, 2.

To permit the quick emptying of chamber, rendered possible by the highair pressure available, said chamber has a horizontal discharge. pipe,13, leading from its lower portion and fitted with several dischargenipples, ll, each'controlled by a flat check valve, 15, and all thusadapted to open at once for emptying the vacuum chamber, 2, when the airpressure is admitted thereto.

I claim 1. In combination with an aerial vessel having a rotatingpropeller and an engine for driving said propeller; a vacuum fuel feeddevice for the-engine comprising a vacuum chamber and a conduit leadingfrom a region of reduced pressure in the air current caused by thepropeller, said conduit opening in the direction of flow of such aircurrent and communicating with said vacuum chamber for exerting suctionthereon.

2. In combination with an aerial vessel having a rotating propeller andan engine the for driving said propeller; .a\"vacuum fuel feed devicefor the engine comprising a vacuum chamber; means for controlling aportion of, the air current caused by the propeller for inducing aregion of low pressure and a passage affording communication betweensuch low pressure region and the said vacuum chamber.

3. In a construction such as defined in claim 2, the said means forcontrolling the air current comprising a Venturi tube interposed in sucha current and the passage to the vacuum chamber leading from a point inthe Venturi tube near its apex.

4. In a construction such as set out in claims 2 and 3, foregoing thesaid passage having its opening in the Venturi tube at a point beyondthe apex plane thereof with 7 reference to the direction of movement ofthe said air current therethrough.

5. In combination with an aerial vessel having a rotating propeller andan engine for driving said propeller; a vacuum fuel feed device for theengine comprising a vacuum chamber and means for producing partialvacuum therein,'and an air inlet connection with said vacuum chamberhaving,

its intake end positioned to receive the air current produced by thepropeller.v

6. In a construction such as set out in claim 5; means for confining aportion of the air currentproduced by the propeller for inducing aregion. of high pressure, said air inlet for the vacuum chamber leadingfrom such region of high pressure.

7. In a construction such as defined in claim 2, the means forcontrolling the air current consisting of a Venturi tube with twopassages leading respectively from points ahead of and behind its apexplane with reference to the direction of flow of said air current, andboth passages leading to said vacuum chamber, together with valvemechanism adapted to afford alternate communication of said passageswith said vacuum chamber. 7,

In testimony whereof I have hereunto set my hand at Chicago, Illinois,this 13th day of December, 1917.

WEBB JAY.

